error: C2139: 'QString': an undefined class is not allowed as an argument to compiler intrinsic type trait '__is_convertible_to'
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@SGaist
No. Not to the best of my understanding of the code that I am working with. By the way, if it helps, the code I am working with was originally written (compiled and executed successfully for Qt4.8).Just now I found one file with include directive #Include <QtCore/QString>.
@Alcor
First please follow @kkoehne's suggestion.It might be time now for you to create a brand new, standalone project in Creator. Keep it tiny, put
#include <QString>at the head of the.cppfile andQString temp;somewhere inside a function. As little else as possible. Try to just compile. Does that work or generate errors? -
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@WWebber: Have you tried the suggestion from @kkoehne in https://forum.qt.io/post/765260 ?
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@WWebber: Have you tried the suggestion from @kkoehne in https://forum.qt.io/post/765260 ?
@aha_1980 said in error: C2139: 'QString': an undefined class is not allowed as an argument to compiler intrinsic type trait '__is_convertible_to':
@WWebber: Have you tried the suggestion from @kkoehne in https://forum.qt.io/post/765260 ?
It points to 'type_traits' and to exactly this line:
struct is_convertible : bool_constant<__is_convertible_to(_From, _To)> {
// determine whether _From is convertible to _To
};1>C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.43.34808\include\type_traits(323,39): error C2139: 'QString': an undefined class is not allowed as an argument to compiler intrinsic type trait '__is_convertible_to'
1>(compiling source file '../QT/test.cpp')
1> c:\Qt6\6.5.3\msvc2019_64\include\QtCore\qcontainerfwd.h(30,7):
1> see declaration of 'QString'
1> C:\Program Files\Microsoft Visual Studio\2022\Professional\VC\Tools\MSVC\14.43.34808\include\type_traits(323,39):
1> the template instantiation context (the oldest one first) is
1> c:\Qt6\6.5.3\msvc2019_64\include\QtCore\qstringtokenizer.h(27,30):
1> while compiling class template member function 'QAnyStringView::QAnyStringView(Container &&,wrapped<Container,QString>::type &&)'
1> c:\Qt6\6.5.3\msvc2019_64\include\QtCore\qstringtokenizer.h(27,30):
1> while processing the default template argument of 'QAnyStringView::QAnyStringView(Container &&,wrapped<Container,QString>::type &&)'
1> c:\Qt6\6.5.3\msvc2019_64\include\QtCore\qanystringview.h(216,35):
1> see reference to alias template instantiation 'QAnyStringView::if_convertible_to<QString,QStringTokenizerBaseBase::tokenizer_state&>' being compiled
1> c:\Qt6\6.5.3\msvc2019_64\include\QtCore\qanystringview.h(82,53):
1> see reference to variable template 'const bool conjunction_v<std::negation<std::disjunction<std::is_same<QStringTokenizerBaseBase::tokenizer_state,enum QAnyStringView::Tag>,std::is_sameQStringTokenizerBaseBase::tokenizer_state,QAnyStringView,std::is_pointerQStringTokenizerBaseBase::tokenizer_state,std::is_sameQStringTokenizerBaseBase::tokenizer_state,QByteArray,std::is_sameQStringTokenizerBaseBase::tokenizer_state,QString > >,std::is_convertible<QStringTokenizerBaseBase::tokenizer_state &,QString> >' being compiled
1> c:\Qt6\6.5.3\msvc2019_64\include\QtCore\qanystringview.h(82,53):
1> see reference to class template instantiation 'std::is_convertible<QStringTokenizerBaseBase::tokenizer_state &,QString>' being compiled -
Use a recent Qt version and add the include to QString before.
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Use a recent Qt version and add the include to QString before.
@Christian-Ehrlicher said in error: C2139: 'QString': an undefined class is not allowed as an argument to compiler intrinsic type trait '__is_convertible_to':
Use a recent Qt version and add the include to QString before.
This is unfortunately not an option as I write a DLL for a main application using V6.5.3.
Even when I just include <qstring> in the testcpp, I'm gettig the same error. -
Simply try a recent version to see if it works...
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Try it with a simple CMakeLists.txt on thee visual studio command line.
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S SGaist has marked this topic as solved
